5 $ msroRr of the sociErr. 



mentioned do not enable mc to ftate. We may nevertheless 

 conjecture, with considerable probability, what the ftep was 

 which immediately followed. 



It mull have occurred to him, as an objection to the confoli- 

 dation of minerals by fubterraneous heat, that many fubftances' 

 are found in the bowels of the earth in a ftate altogether unlike 

 that into which they are brought by the action of our fires at 

 the furface. Coal, for inftance, by exposure to fire, has its parts- 

 diffipated ; the afhes which remain behind are a Substance quite 

 different from the coal itfelf ; and hence it would feem that this 

 foffil can never before have been Subjected to the action of fire. 

 But is it certain, (we may fuppofe Dr Hutton to have faid to* 

 himfelf )> if the heat had been applied to the coal in the interior 

 of the earth, at the bottom of the fea, for example, that the fame 

 diffipation of the parts would have taken place ? Would not the 

 greater compression that muft prevail in that region have pre- 

 vented the diffipation, at leaft till a more intenfe heat was ap- 

 plied ? And if the diffipation was prevented, might not the mafs, 

 after cooling, be very different from any thing that can be ob- 

 tained by burning at the furface of the earth ? It is plain that 

 there is no reafon whatever for answering thefe queftions in the ne- 

 gative. And, on the contrary, if the analogy of nature is consult- 

 ed, if the fact of water requiring more heat to make it boil when 

 it is more eompreffed, or the experiments with Papin's digefter, 

 be considered, it will appear that the anfwer muft be in the 

 affirmative. Nay, it could not but feem reafonable to proceed 

 a ftep farther, and, as the mixture of fubftances is known in fo 

 many instances to promote their fufibility, to fuppofe that when 

 the volatile parts of bodies were reftrained, the whole mafs 

 might be reduced into fufion by heat, though, when thefe fame 

 parts were driven off, the refiduum might be altogether infu- 

 fible. Thus coal, when the charcoal and bitumen are for- 

 ced to remain in union, may very well be a. fufible fubftance,.. 



thoughg. 



